feat: add extension icon

Author: b10902118

extension/icons/128.png

@@ -3,5 +3,8 @@
   "name": "Chrome Inspector Sync",
   "version": "0.0.1",
   "description": "Syncs Chrome DevTools' information with the Chrome Inspector. Currently just $0",
-  "devtools_page": "devtools.html"
+  "devtools_page": "devtools.html",
+  "icons": {
+    "128": "icons/128.png"
+  }
 }